The invention relates to an internal axis crankless rotary piston engine including two rotors mounted eccentrically to one another, one being an external rotor having a mounting with a circularly curved path surrounding a shaft of an internal rotor cooperating therewith.
Rotary piston engines of the aforementioned type are known in the prior art, for example, from U.S. Pat. Nos. 724,665 and 3,954,355, as well as from British Pat. No. 961,872. In the case of an engine of the aforementioned type, the construction principle necessarily involves the path of the two bearings of the external rotor having a relatively large diameter because it surrounds the internal rotor shaft arranged eccentrically thereto unless, in a disadvantageous manner, both rotors are mounted on only one side. The rotor bearings of the known engines are constructed as friction bearings, so that radially they have only a small size. Due to the relatively large diameter of the external rotor bearing, correspondingly high bearing speeds occur, so that known machines can only be used for relatively low rotational speeds and are subject to relatively high friction losses. The use of conventional antifriction bearings for mounting the external rotor would lead to a structurally disadvantageous increase in the radial size of the bearing or to a further increase in the path thereof. In addition, the rotational speed of the engine would be relatively limited, because the large diameter of the path would lead to a correspondingly high rotational speed of the antifriction bearing bodies.
The problem sought to be overcome by the present invention is to obviate the aforementioned disadvantages of known engines, so that they can be operated at much higher rotational speeds and as a result of their small dimensions, they can be used in new fields, e.g. as superchargers or drivers for combustion engines. A further constructional problem sought to be overcome by the invention is to provide the ability to arrange the internal rotor shaft with a greater eccentricity relative to the external rotor and/or to enable it to have a larger diameter.